X-Ray Crystallography

Seeing atoms with interference

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Bragg's law: $2d\sin\theta = n\lambda$.
• X-rays have wavelengths similar to atomic spacings, so crystals diffract them.
• Crystallography revealed salt, DNA and thousands of molecular structures.

Steps

1. Crystals as gratings
2. Find the reflection
3. Measure a spacing
4. Photo 51
5. Harder X-rays
6. Why X-rays?